Had surgery for torn ligament, ankle hurting again, was pregnant. Is this pain due to pregnancy or the surgery?

I had a surgery on my left ankle for torn ligaments that was in 2010 now recently my ankle has been hurting, also my leg has had sharp pain in which my leg has gave out on me, on october 4th 2012 i had my daughter i dont know if maybe the weight gain from that affected my leg and ankle now though i am back down to how much i use to weigh 130 i am 5'6 so i am in a good wieght range but I am having now trouble with my leg and ankle, i am hoping to know what may be going on?